CN107797696B

CN107797696B - Touch panel and organic light emitting display device integrated with touch panel

Info

Publication number: CN107797696B
Application number: CN201710762662.6A
Authority: CN
Inventors: 金龙哲
Original assignee: LG Display Co Ltd
Current assignee: LG Display Co Ltd
Priority date: 2016-08-31
Filing date: 2017-08-30
Publication date: 2021-08-27
Anticipated expiration: 2037-08-30
Also published as: US10503294B2; TWI660372B; KR20180025036A; CN113703617B; US20210165531A1; US10928966B2; KR20230171416A; EP3291072B1; EP3291072A1; TW201812796A; KR102614070B1; CN107797696A; US11334206B2; US20200073503A1; CN113703617A; US20180059843A1

Abstract

Disclosed are a touch panel and an organic light emitting display device integrated with the same, which can solve the problem of retransmission while exhibiting excellent luminance and color viewing angle characteristics. The touch panel includes a plurality of first and second electrodes disposed on a substrate to cross each other. Each of the first and second electrodes includes first and second touch electrodes, respectively. The first touch electrode includes a first metal mesh pattern having a lattice structure formed of a plurality of first and second line electrodes crossing each other and first floating cells disposed in a central portion of the first metal mesh pattern, the first floating cells being electrically isolated from the first metal mesh pattern and made of a transparent conductive material. The second touch electrode includes a second metal mesh pattern formed of a plurality of third and fourth line electrodes crossing each other in a lattice structure and second floating cells disposed in a central portion of the second metal mesh pattern, the second floating cells being electrically isolated from the second metal mesh pattern and made of a transparent conductive material.

Description

Touch panel and organic light emitting display device integrated with touch panel

Cross reference to related applications

This patent application claims the benefit of korean patent application No. 10-2016-0112212, filed on 2016, 8, 31, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to a touch panel and a touch panel-integrated organic light emitting display device, and more particularly, to a touch panel and a touch panel-integrated organic light emitting display device, which reduce a retransmission phenomenon and have high luminance and a wide viewing angle when applied to a display device.

Background

An image display device for displaying various information on a screen has been developed as a core technology of the information communication age, so that the image display device is thinner, lighter, and portable, and exhibits high performance. In addition, an organic light emitting display device that controls the amount of light emitted from an organic light emitting layer to display an image has been highlighted as a flat panel display device, which is lighter in weight and smaller in volume than a Cathode Ray Tube (CRT).

With the self-emissive organic light emitting device, the organic light emitting display device does not require an additional light source, and can be implemented as an ultra-thin display device. Therefore, in recent years, research has been actively conducted on an in-cell (in-cell) touch panel integrated display device that uses an organic light emitting device and includes a touch electrode array in a light emitting cell.

The in-cell touch type touch panel includes first touch electrodes disposed in a first direction and second touch electrodes disposed in a second direction to cross the first touch electrodes. The first touch electrode and the second touch electrode are electrically isolated from each other. When an object having static electricity is in contact with the touch panel, the touch panel senses a touch input by sensing a change in mutual capacitance between the first touch electrode and the second touch electrode.

As the thickness of the touch panel decreases, the thickness of the cover portion covering the upper surface of the touch panel also decreases. As a result, the distance between the first and second touch electrodes and the user's finger is reduced. At this time, parasitic capacitances between the first and second touch electrodes and the user's finger are increased. A retransmission phenomenon of an undesired touch signal due to such a parasitic capacitance occurs, with the result that the touch sensitivity is lowered and a malfunction is caused.

Meanwhile, in manufacturing an organic light emitting display device having a flexible in-cell touch structure, research has been actively conducted on application of a metal mesh pattern exhibiting high flexibility and exhibiting low resistance to a touch electrode. However, since such a metal mesh pattern exhibits a higher reflectivity than a transparent conductive material, the metal mesh pattern is easily seen to the outside, with the result that the overall brightness of the organic light emitting display device is reduced. To solve this problem, a method of aligning a metal mesh pattern with the banks of the non-light emitting areas has been proposed. However, the metal mesh pattern may be misaligned with the display panel. Furthermore, even when the metal mesh pattern is precisely aligned with the display panel, the metal mesh pattern is visible when the viewing angle is increased. Therefore, it is difficult to secure excellent color viewing angle characteristics of the organic light emitting display device.

Disclosure of Invention

Accordingly, the present disclosure is directed to a touch panel and an organic light emitting display device integrated with the touch panel that substantially obviate one or more problems due to limitations and disadvantages of the related art.

An object of the present disclosure is to provide a touch panel and an organic light emitting display device integrated with the touch panel capable of solving a retransmission problem while exhibiting excellent luminance and color viewing angle characteristics.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a touch panel includes a plurality of first electrodes and a plurality of second electrodes disposed on a substrate to cross each other.

Each of the first electrodes may include a first touch electrode including a first metal mesh pattern having a lattice structure formed of a plurality of first line electrodes and a plurality of second line electrodes crossing each other and first floating cells disposed in a central portion of the first metal mesh pattern, the first floating cells being electrically isolated from the first metal mesh pattern, the first floating cells being made of a transparent conductive material.

Each of the second electrodes may include a second touch electrode including a second metal mesh pattern formed of a plurality of third line electrodes and a plurality of fourth line electrodes crossing each other in a lattice structure and second floating cells disposed in a central portion of the second metal mesh pattern, the second floating cells being electrically isolated from the second metal mesh pattern, the second floating cells being made of a transparent conductive material.

The first touch electrodes adjacent to each other in the first direction may be connected to each other via a bridge, and the second touch electrodes adjacent to each other in the second direction may be connected to each other via a connection grid pattern.

The first and second floating cells may be made of a material different from that of the first and second metal mesh patterns. For example, each of the first and second floating units may include transparent conductive patterns arranged crosswise in the third and fourth directions. Third segment electrodes may also be disposed between the transparent conductive patterns. The third segment electrode may be integrally formed with the transparent conductive pattern.

The touch panel according to the present invention may further include a first segment electrode disposed in a contact manner at an intersection of the first and second line electrodes and a second segment electrode disposed in a contact manner at an intersection of the third and fourth line electrodes. Each of the first segment electrode and the second segment electrode may be made of a transparent conductive material.

The touch panel may further include an interlayer dielectric film disposed to cover the first electrode and the second electrode. The interlayer dielectric film may be provided with a plurality of contact holes through which a portion of the edge region of the first metal mesh pattern is exposed. The bridge may electrically connect two first metal mesh patterns adjacent to each other in the first direction through the contact hole.

The bridge may be formed to overlap the connection mesh pattern and the second metal mesh pattern.

Meanwhile, a fourth segment electrode may be further provided on the connection mesh pattern.

In addition, the first metal mesh pattern may further include at least one protrusion protruding from an area thereof adjacent to the second metal mesh pattern toward the second metal mesh pattern, the protrusion having an intersection of the first and second line electrodes. Fifth segment electrodes may also be provided in contact at the intersections of the projections.

In addition, the touch panel may further include at least one floating segment electrode disposed at an interface between the first metal mesh pattern and the second metal mesh pattern, the floating segment electrode being configured to be electrically floating, the floating segment electrode being made of a transparent conductive material.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

fig. 1 is a schematic plan view illustrating a display device including a touch panel according to one embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view taken along line I-I' of FIG. 1 according to one embodiment of the present disclosure;

fig. 3 is a detailed view illustrating a portion a of fig. 1, which illustrates shapes and connection relationships of first and second touch electrodes according to an embodiment of the present disclosure;

fig. 4 is an enlarged plan view illustrating a region B of fig. 3, which illustrates a detailed shape of a floating unit according to an embodiment of the present disclosure;

FIG. 5 is a cross-sectional view taken along line x-x' of FIG. 4 showing an array of touch electrodes according to one embodiment of the present disclosure;

fig. 6a and 6b are enlarged plan views illustrating a region C of fig. 3, which illustrates a bridge and a connection structure connecting grid patterns according to an embodiment of the present disclosure;

FIG. 7 is a cross-sectional view of the touch electrode array taken along line y-y' of FIG. 6b according to one embodiment of the present disclosure;

FIG. 8 is an enlarged plan view of region D of FIG. 3, illustrating an interface between a first touch electrode and a second touch electrode according to one embodiment of the present disclosure; and

fig. 9a is a graph illustrating luminance and color viewing angle characteristics of an organic light emitting display device to which a conventional touch panel is applied, and fig. 9b is a graph illustrating luminance and color viewing angle characteristics of an organic light emitting display device to which a touch panel according to the present invention is applied.

Detailed Description

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may obscure the subject matter of the present invention. Further, terms used in the following description are selected in consideration of ease of preparation of the specification, and may be different from names of components constituting an actual product.

It will be understood that when an element is referred to as being "on" another element, it can be directly on the element or one or more intervening layers or elements may also be present therebetween. In contrast, it will be understood that when an element is referred to as being "in contact with" another element, there are no intervening elements or layers present therebetween.

The size and thickness of each element shown in the drawings are given only for convenience of description, and the present invention is not limited thereto.

Hereinafter, a display device including a touch panel according to the present invention will be described with reference to the accompanying drawings.

Fig. 1 is a schematic plan view illustrating a display device including a touch panel according to the present disclosure.

The touch panel according to the present disclosure includes a plurality of first electrodes 101 arranged in a first direction on a substrate 1000 and a plurality of second electrodes 102 arranged in a second direction crossing the first direction. In the present embodiment, the first direction is shown as a horizontal direction, and the second direction is shown as a vertical direction. However, the present invention is not limited thereto.

The first electrode 101 includes first touch electrodes 1011 continuously arranged in the first direction. First touch electrodes adjacent in the first direction among the first touch electrodes 1011 are connected to each other via a bridge 912. In addition, the second electrode 102 includes a second touch electrode 1021 and a connection grid pattern 1027 continuously arranged in the second direction. The first electrode 101 including the first touch electrode 1011 may serve as a touch electrode for applying a touch signal, and the second electrode 102 including the second touch electrode 1021 may serve as a sensing electrode for sensing the touch signal. However, the present invention is not limited thereto.

The first and

second touch electrodes

1011 and 1021 and the connection relationship therebetween will be described in detail below.

The first electrode 101 is connected to the pad electrode 110 of the touch pad unit 2350 via a first wiring line 111a, and the second electrode 102 is connected to the pad electrode 110 of the touch pad unit 2350 via a second wiring line 111 b. In the present embodiment, the paired first electrodes 101 adjacent to each other in the vertical direction are connected in parallel with one of the first wiring lines 111a so as to be commonly connected to the pad electrode 110, and the paired second electrodes 102 adjacent to each other in the horizontal direction are connected in parallel with one of the second wiring lines 111b so as to be commonly connected to the pad electrode 110. However, the present invention is not limited thereto. As described above, in the case where the first electrode 101 and the second electrode 102 are connected to the pad electrode 110 in pairs, the pair of first touch electrodes 1011 and the pair of second touch electrodes 1021 arranged to intersect the pair of first touch electrodes 1011 are driven as the unit sensors U for sensing a set of touch coordinates.

Fig. 2 is a schematic sectional view taken along line I-I' of fig. 1.

The display device according to the present disclosure is configured to have an in-cell structure in which the touch electrode array 230 is implemented in a display panel. In this embodiment mode, an organic light-emitting display device having an in-cell structure is described by way of example. However, the present invention is not limited thereto. The display device according to the present disclosure is configured such that the first substrate 120, the first buffer layer 130, the thin film transistor array 140, and the organic light emitting array 150 are sequentially disposed on the substrate 1000, and such that the passivation layer 160 is provided to cover the organic light emitting array 150. The second substrate 210, the second buffer layer 220, and the touch electrode array 230 are disposed within the cover glass 3000. The touch electrode array 230 is laminated to the passivation layer 160 disposed on the organic light emitting array 150 via the bonding layer 400 to be opposite to the organic light emitting array 150.

Each of the first and second buffer layers 130 and 220 includes an active region and a dead region. The touch electrode array 230, the organic light emitting array 150, and the thin film transistors in the thin film transistor array 140 are formed in the active region, except for the pad unit. The touch pad unit and the pad unit of the thin film transistor array are formed in a portion of the dead region.

The first substrate 120 and the second substrate 210 are used to prevent damage to the array therein during a laser application or etching process. According to circumstances, the substrate 1000 and the cover glass 3000 are removed, and the first substrate 120 and the second substrate 210 serve to protect the display device from the outside. Each of the first substrate 120 and the second substrate 210 may be made of a polymer material such as polyimide or photo acryl (photo acryl).

Each of the first and second buffer layers 130 and 220 is formed by sequentially stacking the same kind of inorganic films, for example, oxide films (SiO films)₂) Or nitride film (SiN)_x) Or by alternately stacking different kinds of inorganic films. Each of the first and second buffer layers 130 and 220 serves as a barrier to prevent moisture or external air from penetrating into the organic light emitting array 150 in a subsequent process of laminating the upper substrate to the lower substrate.

The touch electrode array 230 and the touch pad unit 2350 are formed in the same surface of the second buffer layer 220. The touch pad unit 2350 is connected to a pad unit (not shown) of the thin film transistor array 140 via an encapsulant 450 including a conductive ball 455 during the upper and lower lamination using the bonding layer 400. The bonding layer 400 has an anti-permeation function. In addition, the bonding layer 400 directly contacts the passivation layer 160 covering the organic light emitting array 150. Accordingly, the bonding layer 400 serves to more reliably prevent external air and moisture from penetrating into the organic light emitting array 150 in addition to the role of the passivation layer 160.

The thin film transistor array 140 including the pad unit is formed such that one side thereof protrudes more than the touch electrode array 230. The reason for this is that a driving Integrated Circuit (IC) (not shown) for transmitting a signal for simultaneously driving the touch electrode array, the thin film transistor array, and the organic light emitting array is provided at the protruding portion thereof. Although not shown, the thin film transistor array driving pad and the dummy pad include a plurality of dummy electrodes connected to the driving IC via wirings. After the glass is removed, the driving IC is connected to a Flexible Printed Circuit Board (FPCB) by bonding to be controlled by a Micro Control Unit (MCU) (not shown) and a timing controller (not shown) provided at the FPCB. The dummy pad is formed in a portion of the dead region outside the active region corresponding to the touch pad cell on the same layer as the metal constituting the gate line or the data line.

The driving circuit may be mounted on a flexible printed circuit board or an Anisotropic Conductive Film (ACF) using a Chip On Film (COF) method.

Although not shown, the thin film transistor array driving pad and the dummy pad are connected to each other via a wiring (not shown) formed on the flexible printed circuit board or the lower substrate 1000. In addition, the flexible printed circuit board may be further provided with a controller (not shown) for controlling the driving circuit.

The dummy pad is formed in a portion of a dead region outside the active region corresponding to a touch pad cell on the same layer as a metal constituting the gate line or the data line.

Fig. 3 is a detailed view showing a portion a of fig. 1, and illustrates shapes and connection relationships of the first touch electrode 1011 and the second touch electrode 1021.

The first touch electrode 1011 according to the present disclosure includes first

metal mesh patterns

1012a and 1012b having a lattice structure formed by a plurality of first and

second line electrodes

1031 and 1032 crossing in third and fourth directions and first floating

cells

1014a and 1014b disposed in central portions of the first

metal mesh patterns

1012a and 1012b to be electrically isolated from the first

metal mesh patterns

1012a and 1012 b. The first floating

units

1014a and 1014b may be made of a different material from the first

metal mesh patterns

1012a and 1012 b. For example, the first floating

cells

1014a and 1014b may be made of a transparent conductive material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Indium Gallium Zinc Oxide (IGZO), or zinc oxide (ZnO). However, the present invention is not limited thereto.

The first metal mesh pattern 1012a disposed at one side and the first metal mesh pattern 1012b disposed at the other side adjacent to the first metal mesh pattern 1012a in the first direction are electrically connected to each other via a bridge 912.

The

first split electrodes

1013a and 1013b may also be disposed in a contacting manner at intersections of the first and

second line electrodes

1031 and 1032 in the third and fourth directions. The

first split electrodes

1013a and 1013b may be omitted according to design.

The second touch electrode 1021 according to the present disclosure includes second

metal mesh patterns

1022a and 1022b having a lattice structure formed by a plurality of third and

fourth line electrodes

1033 and 1034 crossing in third and fourth directions, and second floating

units

1024a and 1024b disposed in central portions of the second

metal mesh patterns

1022a and 1022b to be electrically isolated from the second

metal mesh patterns

1022a and 1022 b. As with the first floating

units

1014a and 1014b, the second floating

units

1024a and 1024b may be made of a different material than the second

metal grid patterns

1022a and 1022 b. For example, the second floating

units

1024a and 1024b may be made of a transparent conductive material such as ITO, IZO, IGZO, or ZnO. However, the present invention is not limited thereto.

The first and

second touch electrodes

1011 and 1021 of the touch electrode array 230 according to the embodiment of the present disclosure are formed on the same layer to be electrically isolated from each other. However, the present invention is not limited thereto.

In this embodiment, the third direction and the fourth direction are diagonal directions. However, the present invention is not limited thereto.

The second metal mesh pattern 1022a disposed at one side and the second metal mesh pattern 1022b disposed at the other side adjacent to the second metal mesh pattern 1022a in the second direction are electrically connected to each other via a connection mesh pattern to be described below.

Second segment electrodes

1023a and 1023b may also be disposed in contact at intersections of second

metal mesh patterns

1022a and 1022b in the first and second directions. The

second segment electrodes

1023a and 1023b may also be omitted according to design.

Each of the first and

second touch electrodes

1011 and 1021 according to the embodiment of the present disclosure has a diamond shape. Each of the first and second metal mesh patterns 1012 and 1022 and the first and second floating units 1014 and 1024 also has a diamond shape. The diamond shape may be changed according to the structure of each pixel of the display panel. When each pixel of the display panel has a diamond shape, each of the first and

second touch electrodes

1011 and 1021 and the first and second metal mesh patterns 1012 and 1022 may be formed to have a diamond shape. In addition, each of the first and second

segmented electrodes

1013a and 1013b and 1023a and 1023b, which are in contact with the intersections of the first and second metal mesh patterns 1012 and 1022, may also have a diamond shape. Since each element constituting the first and

second touch electrodes

1011 and 1021 including the first and second metal mesh patterns 1012 and 1022 has a diamond shape, the metal mesh patterns can be prevented from being visible. The first and second metal mesh patterns 1012 and 1022 do not overlap the opening in each pixel, but are disposed to overlap the non-display area or the black matrix of each pixel, thereby minimizing the visibility of the metal mesh patterns.

However, the first and second metal mesh patterns 1012 and 1022 may be visible to a viewer according to the viewing angle of the viewer at an arbitrary viewing position. Accordingly, the first and second metal mesh patterns 1012 and 1022 are visible at a viewing angle equal to or greater than a predetermined level, thereby reducing a luminance viewing angle and a color viewing angle. In the embodiment of the invention, each of the first and second floating units 1014 and 1024 is made of a transparent conductive material, thereby minimizing visibility of the first and second metal mesh patterns 1012 and 1022 even when the viewing angle is changed.

Meanwhile, the touch panel according to the embodiment of the invention includes first floating

units

1014a and 1014b electrically isolated from the first touch electrode 1011 and second floating

units

1024a and 1024b electrically isolated from the second touch electrode 1021. The first floating

units

1014a and 1014b reduce the effective electrode area of the first touch electrode 1011, thereby reducing the parasitic capacitance between the finger and the first touch electrode 1011. In addition, the second floating

units

1024a and 1024b reduce the effective electrode area of the second touch electrode 1021, thereby reducing the parasitic capacitance between the finger and the second touch electrode 1021. Accordingly, in the touch panel according to the embodiment of the present invention, the retransmission phenomenon can be reduced. As the area of the floating unit increases, the retransmission phenomenon can be further reduced. However, if the area of the floating unit is too large, the area of the touch electrode is excessively reduced, and thus touch sensitivity may be reduced. Therefore, in the touch panel according to the present invention, in order to maintain touch sensitivity while solving the retransmission problem, a predetermined area ratio of the floating unit to the touch electrode may be set. For example, the area ratio of the floating unit with respect to the

touch electrodes

1011 and 1021 may be about 10 to 65%.

In the touch panel according to the present invention, each of the first and second metal mesh patterns 1012 and 1022 may be made of any one selected from molybdenum, aluminum, chromium, gold, titanium, neodymium, and copper or an alloy thereof. Since the resistance of each of the first and second metal mesh patterns 1012 and 1022 is low, the RC delay of the touch panel may be reduced. In addition, since the metal material has high flexibility, the touch panel according to the present invention may be applied to a flexible display device.

Further, when the touch panel according to the present invention includes the first and second segment electrodes 1013 and 1023 disposed to contact the first and second metal mesh patterns 1012 and 1022, the effective capacitance of each of the first and second metal mesh patterns 1012 and 1022 is increased because each segment electrode has a touch electrode surface, thereby improving the touch sensitivity of the touch panel.

Fig. 4 is an enlarged plan view showing a region B of fig. 3, showing detailed shapes of the first floating unit 1014 and the second floating unit 1024. The second floating unit 1024b shown in fig. 4 is disposed in the second touch electrode 1021, and has the same structure as the floating

units

1014a and 1014b disposed in the first touch electrode 1011.

Referring to fig. 4, the second floating unit 1024b includes transparent conductive patterns 1025 arranged to cross in the first and second directions and third segment electrodes 1026 arranged in a contact state between the transparent conductive patterns 1025. The third segmented electrode 1026 may be omitted depending on the design. In this case, the transparent conductive patterns 1025 cross in the third and fourth directions to be connected in a line like the shape of the first and

second line electrodes

1031 and 1032.

FIG. 5 is a cross-sectional view taken along line x-x' of FIG. 4, showing touch electrode array 230. The structure outside the buffer layer 220 is omitted for convenience. In fig. 5, only the second floating unit 1024b of the second touch electrode 1021 is shown. However, the first floating

units

1014a and 1014b of the first touch electrode 1011 also have the same portion.

Referring to fig. 5, the second metal mesh pattern 1022b is formed on the buffer layer 220. The second segment electrodes 1023b are formed at the intersections of the line electrodes of the second metal mesh pattern 1022b in a contacting manner. The transparent conductive pattern 1025 and the third segment electrode 1026 of the second floating unit 1024b are simultaneously formed when the second segment electrode 1023b is formed. Since the transparent conductive pattern 1025 and the third segment electrode 1026 are made of a transparent conductive material such as ITO, IZO, IGZO, ZnO, or the like, the transparent conductive pattern 1025 and the third segment electrode 1026 may be simultaneously formed.

An interlayer dielectric film 232 is formed on the entire surface of the buffer layer 220 including the transparent conductive pattern 1025 and the third segment electrode 1026 of the second metal mesh pattern 1022b and the second floating unit 1024 b. A passivation layer 233 is also formed on the interlayer dielectric film 232.

In the cross-sectional view of fig. 5, the buffer layer 220 is disposed on the lower side. However, when the touch electrode array 230 is actually laminated to the organic light emitting array 150 and the passivation layer 160, the structure of fig. 5 is reversed. That is, the actual portion of touch electrode array 230 taken along line x-x' is horizontally inverted from the structure of FIG. 5.

As can be seen from fig. 4 and 5, the second floating units 1024b are electrically isolated from the second metal mesh pattern 1022 b. Therefore, as described above, the floating unit reduces the effective area of the touch electrode, thereby reducing parasitic capacitance and a re-emission phenomenon affecting the touch panel. Further, since the floating unit is made of a transparent conductive material, the floating unit is not visible at any viewing angle, and thus a color viewing angle and a luminance viewing angle are increased as compared with the case where the second floating unit 1024b has a metal mesh pattern.

Fig. 6a and 6b are enlarged plan views illustrating a region C of fig. 3, showing a bridge 912 and a connection structure connecting the mesh patterns 1027.

As shown in fig. 6a, two first touch electrodes adjacent to each other in the first direction are connected to each other via a bridge 912, and two second touch electrodes adjacent to each other in the second direction are connected to each other via a connection grid pattern 1027. The connection mesh pattern 1027 is formed on the same layer as the first

metal mesh patterns

1012a, 1012b and the second

metal mesh patterns

1022a and 1022b, and is made of the same material as the first

metal mesh patterns

1012a, 1012b and the second

metal mesh patterns

1022a and 1022 b. The connection mesh pattern 1027 extends from the third and fourth wire electrodes constituting the second

metal mesh patterns

1022a and 1022b, and is formed in a shape in which two wire electrodes cross.

Therefore, the connection grid pattern 1027 has the following structure: in this structure, two second

metal mesh patterns

1022a and 1022b adjacent to each other in the second direction are connected to each other using two wire electrodes. However, the present invention is not limited thereto.

The bridge 912 is electrically isolated from the connection grid pattern 1027. As shown in fig. 6b, the bridge 912 is formed to have a shape overlapping with a position where the mesh pattern 1027 is connected. Similar to the connection mesh pattern 1027 formed in a shape in which two wire electrodes cross, the bridge 912 may be formed to overlap with positions of two wire electrodes constituting the connection mesh pattern 1027. The bridge 912 is formed to overlap the connection mesh pattern 1027, and even to overlap a portion of the second

metal mesh patterns

1022a and 1022b and a portion of the first

metal mesh patterns

1012a and 1012 b. In addition, the bridge 912 is connected to the first

metal mesh patterns

1012a and 1012b via the contact holes 1042. The bridge 912 may be made of the same material as the first and second metal mesh patterns 1012 and 1022. A plurality of bridges 912 may be provided.

This will be described in more detail with reference to fig. 7.

FIG. 7 is a cross-sectional view of the touch electrode array 230 taken along line y-y' of FIG. 6 b. The structure outside the buffer layer 220 is omitted for convenience.

Referring to fig. 7, first

metal mesh patterns

1012a and 1012b, second

metal mesh patterns

1022a and 1022b, and a connection mesh pattern 1027 connecting the second

metal mesh patterns

1022a and 1022b are formed on the buffer layer 220.

The

first segment electrodes

1013a and 1013b may also be provided to contact the first

metal mesh patterns

1012a and 1012 b. In addition,

second segment electrodes

1023a and 1023b may be further disposed to contact the second

metal mesh patterns

1022a and 1022b, and a fourth segment electrode 1028 may be further disposed to contact the connection mesh pattern 1027.

The interlayer dielectric film 232 is formed on the entire surface of the buffer layer 220 including the first and second metal mesh patterns 1012 and 1022 and the first and second segment electrodes 1013 and 1023. The interlayer dielectric film 232 is provided with a contact hole 1042, and two adjacent first

metal mesh patterns

1012a and 1012b are exposed through the contact hole 1042. A bridge 912 is formed on the interlayer dielectric film 232 to connect the two contact holes 1042.

A passivation layer 233 is disposed on the interlayer dielectric film 232, including on the bridge 912.

In practice, the touch electrode array 230 shown in fig. 7 is laminated on the organic light emitting array 150 and the passivation layer 160 in an opposite state. Thus, in practice, the touch electrode array 230 shown in fig. 7 has the reverse form of the structure of fig. 7.

As described above, the connection mesh pattern 1027 extends from the second

metal mesh patterns

1022a and 1022b so as to have a shape in which two wire electrodes cross. That is, the connection mesh pattern 1027 may also be linearly formed in the non-display area or the black matrix area of each pixel so as not to overlap the opening area of each pixel, thereby minimizing the visibility of the connection mesh pattern 1027.

The bridge 912 also has a curved linear structure so as to overlap the first and second metal mesh patterns and the connection mesh pattern. Accordingly, the bridge 912 is also formed in the non-display area or the black matrix area of each pixel so as not to overlap the opening area of each pixel, thereby minimizing visibility of the bridge to the viewer.

Meanwhile, in fig. 6a and 6b, the bridge 912 is shown as directly connecting the first metal mesh pattern. Alternatively, the bridge 912 may be connected to the first segment electrode on the first metal mesh pattern so as to electrically connect the adjacent first touch electrodes.

Fig. 8 is an enlarged plan view region D of fig. 3, illustrating an interface between the first touch electrode 1011 and the second touch electrode 1021.

As shown in fig. 8, the first metal mesh pattern 1012a includes at least one protrusion 1052 protruding from an interface with the second metal mesh pattern 1022a of the second touch electrode 1021 toward the second metal mesh pattern 1022a and having an intersection of the first and

second line electrodes

1031 and 1032. Fifth segment electrodes 1041 may be further provided at intersections of the projections 1052.

The two first touch electrodes 1011 adjacent to each other in the first direction are connected to each other via the bridge 912, and the two second touch electrodes 1021 adjacent to each other in the second direction are connected to each other via the connection grid pattern 1027. At this time, the second touch electrode 1021 of each second electrode 102 may be further provided with a connection mesh pattern 1027 and a fourth segment electrode 1028, whereby the second electrode 102 may have a larger effective area than the first electrode 101 in its designed structure. In this case, in order to improve the touch sensitivity, the effective area of the first touch electrode 1011 constituting the first electrode 101 may be increased.

In order to increase the effective area of the first touch electrode 1011, the first metal mesh pattern 1012a constituting the first touch electrode 1011 includes protrusions 1052 protruding toward the second metal mesh pattern 1022a, and the second metal mesh pattern 1022b is formed in a structure having recesses corresponding to the protrusions 1052. That is, since the protrusion 1052 is included in the first metal mesh pattern 1012a, the effective areas of the first and second electrodes 101 and 102 are adjusted, whereby the touch sensitivity is improved.

Meanwhile, in order to further improve the luminance and viewing angle characteristics, at least one floating segment electrode 1051 may be disposed between the first and second

metal mesh patterns

1012a and 1022 a. The floating segment electrode 1051 may also be made of a transparent conductive material such as ITO, IZO, IGZO, or ZnO. The floating segment electrode 1051 may be disposed at each of the first metal mesh patterns 1012 a. The floating segment electrode 1051 may be formed to include transparent conductive patterns and segment electrodes disposed therebetween, such as the first and second floating cells 1014 and 1024. However, the present invention is not limited thereto.

In the display device to which the touch electrode array 230 is applied by the floating segment electrode 1051, further improvement in luminance and viewing angle characteristics can be expected.

As shown in fig. 9a and 9b, it can be seen that the maximum luminance of the organic light emitting display device to which the touch panel according to the present invention is applied is higher than that of the organic light emitting display device to which the conventional touch panel is applied, and thus, the luminance reduction phenomenon due to the increase of the viewing angle is also reduced.

Further, it can be seen that the change of the color coordinate Δ U 'V' due to the change of the viewing angle of the organic light emitting display device to which the touch panel according to the present invention is applied is much lower than the change of the color coordinate Δ U 'V' of the organic light emitting display device to which the conventional touch panel is applied.

Accordingly, the organic light emitting display device to which the touch panel according to the present invention is applied has the following effects: luminance and a luminance viewing angle are increased and a change in color coordinates due to a change in viewing angle is minimized, thereby improving color viewing angle characteristics compared to the conventional art.

As apparent from the above description, the present invention has the following effects. When each pixel has a diamond shape and each of the first and second touch electrodes including the first and second metal mesh patterns has a diamond shape, the metal mesh patterns may be prevented from being visible. The first and second metal mesh patterns do not overlap the opening in each pixel, but are disposed to overlap the non-display area or the black matrix of each pixel, thereby minimizing visibility of the metal mesh patterns.

In the touch panel according to the present invention, each of the first and second floating units is made of a transparent conductive material, thereby minimizing visibility of the metal mesh pattern even when a viewing angle is changed.

Meanwhile, the touch panel according to the present invention includes a first floating unit electrically isolated from the first touch electrode and a second floating unit electrically isolated from the second touch electrode. The first floating unit reduces an effective electrode area of the first touch electrode, thereby reducing a parasitic capacitance between the finger and the first touch electrode. In addition, the second floating unit reduces an effective electrode area of the second touch electrode, thereby reducing a parasitic capacitance between the finger and the second touch electrode. Accordingly, in the touch panel according to the embodiment of the present invention, the retransmission phenomenon can be reduced.

Since the resistance of each of the first and second metal mesh patterns is low, the RC delay of the touch panel may be reduced. In addition, since the metal material exhibits high flexibility, the touch panel according to the present invention may be applied to a flexible display device.

Further, when the touch panel according to the present invention includes segment electrodes disposed to contact the first and second metal mesh patterns, an effective capacitance of each of the first and second touch electrodes is increased, thereby improving a touch sensitivity of the touch panel since each segment electrode has a touch electrode surface.

The connection mesh pattern extends from the second metal mesh pattern so as to have a shape in which the two line electrodes cross. That is, the connection mesh pattern may also be linearly formed in the non-display area or the black matrix area of each pixel so as not to overlap the opening area of each pixel, thereby minimizing the visibility of the connection mesh pattern.

The bridge also has a curved linear structure so as to overlap the first and second metal mesh patterns and the connection mesh pattern. Therefore, the bridge is also formed in the non-display area or the black matrix area of each pixel so as not to overlap the opening area of each pixel, thereby minimizing the visibility of the bridge to the viewer.

In the touch panel according to the present invention, the protrusion is included in the first metal mesh pattern, thereby adjusting the effective areas of the first and second electrodes and improving the touch sensitivity.

Further, in the touch panel according to the present invention, a greater improvement in luminance and viewing angle characteristics can be expected due to the floating segment electrodes.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A touch panel, comprising:

a plurality of first electrodes arranged on the substrate in a first direction; and

a plurality of second electrodes arranged in a second direction crossing the first direction, the second electrodes being electrically isolated from the first electrodes,

each of the first electrodes includes a first touch electrode including a first metal mesh pattern having a lattice structure and first floating cells disposed in a central portion of the first metal mesh pattern, the first floating cells being electrically isolated from the first metal mesh pattern, the first floating cells being made of a transparent conductive material different from a material of the first metal mesh pattern and having a reflectance lower than that of the material of the first metal mesh pattern, and

each of the second electrodes includes a second touch electrode including a second metal mesh pattern having a lattice structure and second floating cells electrically isolated from the second metal mesh pattern, the second floating cells being made of a transparent conductive material different from a material of the second metal mesh pattern and having a reflectivity lower than a reflectivity of a material of the second metal mesh pattern.

2. The touch panel according to claim 1,

the first metal mesh pattern includes a plurality of first line electrodes and a plurality of second line electrodes crossing in third and fourth directions to form a lattice structure, and

the second metal mesh pattern includes a plurality of third line electrodes and a plurality of fourth line electrodes, which intersect in the third direction and the fourth direction to form a lattice structure.

3. The touch panel according to claim 1,

each of the first electrodes includes a bridge for connecting the first touch electrodes adjacent to each other in the first direction, and

each of the second electrodes includes a connection grid pattern for connecting the second touch electrodes adjacent to each other in the second direction.

4. The touch panel according to claim 1, wherein each of the first floating unit and the second floating unit includes transparent conductive patterns arranged crosswise in a third direction and a fourth direction.

5. The touch panel of claim 2, further comprising:

a first segment electrode disposed in a contacting manner at an intersection of the first and second line electrodes; and

a second segment electrode disposed in contact at an intersection of the third and fourth wire electrodes.

6. The touch panel according to claim 5, wherein each of the first segment electrode and the second segment electrode is made of a transparent conductive material.

7. The touch panel of claim 4, further comprising segmented electrodes disposed in contact with the transparent conductive pattern.

8. The touch panel of claim 7, wherein the segment electrodes are integrally formed with the transparent conductive pattern.

9. The touch panel of claim 3, further comprising:

an interlayer dielectric film provided to cover the first and second electrodes, the interlayer dielectric film being provided with a plurality of contact holes through which a portion of an edge region of the first metal mesh pattern is exposed, wherein the bridge electrically connects two first metal mesh patterns adjacent to each other in the first direction through the contact holes.

10. The touch panel according to claim 9, wherein the bridge is disposed to overlap the second metal mesh pattern and the connection mesh pattern.

11. The touch panel of claim 3, further comprising segmented electrodes disposed on the connecting grid pattern.

12. The touch panel according to claim 2, wherein the first metal mesh pattern further comprises at least one protrusion protruding from an area thereof adjacent to the second metal mesh pattern toward the second metal mesh pattern, the protrusion having an intersection of the first and second line electrodes.

13. The touch panel of claim 12, further comprising segmented electrodes disposed in contact at intersections of the protrusions.

14. The touch panel of claim 1, further comprising at least one floating segment electrode disposed at an interface between the first and second metal mesh patterns, the floating segment electrode configured to electrically float, the floating segment electrode made of a transparent conductive material.

15. An organic light emitting display device comprising:

a thin film transistor array disposed on the substrate;

an organic light emitting array on the thin film transistor array; and

the touch panel according to any one of claims 1 to 14, which is laminated to the organic light emitting array via a bonding layer so as to be opposed to the organic light emitting array.